I have problem with adsense

I tried using adsense to show my ads but it didn't work.
So I am now trying to use widget to show up my ads but it's not loading either.
How do I make it show my ads show up? PLEASE!!!
Here's my code for the widget:
<script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>
<!-- nodebb_top -->
<ins class="adsbygoogle"
style="display:block"
data-ad-client="ca-pub-xxxxxxxxxxxx"
data-ad-slot="xxxxxxxxxxxx"
data-ad-format="auto"></ins>
<script>
(adsbygoogle = window.adsbygoogle || []).push({});
</script>